CVE-2026-62963CWE-409

Centrifugo: Decompression bomb DoS via permessage-deflate in unidirectional WebSocket transport

High · published July 16, 2026

CVSS v4.0
8.7
EPSS
1%
Percentile
43.6
In the wild
Unconfirmed
What it is

Centrifugo is an open-source scalable real-time messaging server. Prior to 6.8.4, Centrifugo unidirectional WebSocket transport with uni_websocket.compression enabled enforced uni_websocket.message_size_limit against compressed wire-frame length in internal/websocket/conn.go advanceFrame, but ReadMessage used io.ReadAll after decompression without an output cap, allowing unauthenticated requests to /connection/uni_websocket to trigger large memory and CPU consumption. This issue is fixed in version 6.8.4.

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
EPSS
0.00524 · 43.6th percentile
Weakness
CWE-409 · Improper Handling of Highly Compressed Data (Data Amplification)
Published
2026-07-16T19:34Z
EPSS history
Timeline
  • 16 JUL 19:34Z
    Centrifugo: Decompression bomb DoS via permessage-deflate in unidirectional WebSocket transport
    cvelistv5